Re: expected baseline changes for forky => proposal no more FPU and 80bits float/double on i386

On Fri, 14 Aug 2026 at 11:15:33 +0200, John Paul Adrian Glaubitz wrote:
>On Fri, 2026-08-14 at 10:59 +0200, Bastien Roucaries wrote:
>> It is not a baseline raise in this case, it is do not use FPU by default
>>
>
>Is there a source where I can read more on this proposal?

When Bastien refers to "do not use FPU by default" here, I think that 
could be more precisely stated as "do not use the i387 FPU instructions 
for arithmetic by default". In other words, the current default on i386 
is -mfpmath=387 -march=i686, and the proposal is to change that to 
either -mfpmath=sse -march=x86-64 or -mfpmath=sse -march=pentium4.

This is consistent with the Debian 13 release notes having already said 
that legacy 32-bit binaries on x86_64 hardware are the only remaining 
supported use-case for the i386 port:
https://www.debian.org/releases/trixie/release-notes/issues.en.html#reduced-support-for-i386

The actual proposal: 
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1127352

     smcv